The accumulating dents and dings on Curiosity’s wheels.
The accumulating dents and dings on Curiosity’s wheels.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The accumulating dents and dings on Curiosity’s wheels.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
This is interesting to me because of the wheel material and conditions. I’ve worked with .030″ aluminum in various alloys for many years and find the dents and punctures a bit strange. They only note that the aluminum is “aircraft” grade – which means nothing – but don’t specify the alloy, and that’s important. I can only visualize denting the skin of the wheel if the full weight on it was born upon a very small sharp, hard pointed/jagged material. Actually puncturing/fracturing/tearing the skin would be more likely with the hard/brittle alloys.
Does anyone know the total weight on the left front wheel? (moon weight)
I couldn’t readily find c.g. information on the rover, but because all wheels are driven, and the claimed ‘tip over’ angle is 50 degrees in any direction, it’s reasonable to assume that the vehicle weight is more-or-less evenly distributed among the six wheels. This would make any given wheel’s share of the load about 56 kg on Mars. (Based on an Earth mass of 899 kg and comparing Mars’ gravity of 3.7 m/s/s/ to Earth’s 9.8 m/s/s).
Thanks for doing what I should have done in the first place – looking up to Earth weight of the entire vehicle. I wasn’t aware it was nearly a ton. With ~125lbs. bearing down on each wheel I can imagine the penetration occurring if a hard, raised point of ~1/8″ is rolled over with most .030″ alloys.